申論題

(c) Consider the following steady, two-dimensional (in x-y plane), circular flows. The velocity components are expressed in cylindrical coordinate (in 2D r - θ plane; r is radial distance, e is the angle from the x-axis)
 (1) Flow in solid-body rotation: u_r =0 u₀, = ωr (ω is a constant)
(2) Line vortex:u_r, =0   uθ -=k/r (k is a constant)
 Sketch the velocity field and calculate the vorticity. (8 points)